Gloves with a visual indicator to remind change

ABSTRACT

Thin wall gloves have color change time indicators. A color change label or friendly reminding message can be seen after the glove is put on for a period of time. The warning indicators can be triggered via UV, visible light, temperature change, air exposure, presence of oxidizers (oxygen, chlorine), pH change, chemical reaction of two components or any combination of these activators. The method for producing these gloves can be easily realized under common glove production lines. Depending on the desired applications, both powdered and powder free gloves can be produced.

CROSS-REFERENCED APPLICATION

The present application claims the priority of provisional patentapplication Ser. No. 60/611,293, filed Sep. 21, 2004.

BACKGROUND OF THE INVENTION

Single use disposable gloves have been widely used in many fields andindustries to provide necessary hand protection and to avoid crosscontamination. It is a common practice to frequently change gloves,because thin wall gloves may fail after a prolong period of time, orcross contamination may be induced with more than one substance orobject being handled.

It is desirable to have some kind of warning indicator to provide betterprotection. There are a number of mechanisms and methods that have beenproduced.

For example, a glove with multiple layers can be made with a coloredliquid in between the layers, as shown in U.S. Pat. No. 6,370,694. Oncethe glove is punctured half way through, the colored liquid will flowout and be seen. Another example is a glove with multiple layers with avacuum in between. Once the glove is punctured halfway through, theglove becomes inflated. These inventions provide better protectionagainst glove failures caused by punctures.

U.S. Pat. No. 6,744,368 describes another breach detecting glove. Again,a liquid is sealed in between multiple layers, and a microchip isembedded into gloves. Once the glove fails, the sealed in liquid willactivate the microchip which, in turn, will communicate the compromisedintegrity of the glove to the wearer.

All these methods deal with a glove damaged by punctures. They allassume that the puncture occurs half way through the glove, so that thewearer can be protected by a prompt glove change. Obviously, that is notalways the case, not to mention when the liquid flowing out causescontamination.

It would be desirable to have an indicator that can remind the wearersto change gloves before the glove barrier integrity is compromised.

It is an object of the invention to provide a time sensitive indicatoron a glove.

It is another object of the invention changing color with time to signalthe need to change gloves.

It is still another object of the invention to provide a glove with avisual indication of the amount of time a glove has been worn.

It is yet another object of the invention to provide length of timeindicators triggered by any number of activators.

SUMMARY OF THE INVENTION

Thin wall gloves have color change time indicators. A color change labelor friendly reminding message can be seen after the glove is put on fora period of time. The warning indicators can be triggered via UV,visible light, temperature change, air exposure, presence of oxidizers(oxygen, chlorine), pH change, chemical reaction of two components orany combination of these activators. The method for producing thesegloves can be easily realized under common glove production lines.Depending on the desired applications, both powdered and powder freegloves can be produced.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 displays a glove having an activated warning sign;

FIG. 2 displays a glove having an appearing warning sign; and

FIG. 3 displays a glove having a progressive warning sign.

DETAILED DESCRIPTION OF INVENTION

Many industries and applications use color changing labels and printinginks. The triggering mechanism can be exposure to light, heat, moisture,chemical reaction of two components, and some component of air, such asoxygen or carbon dioxide. Colorless indication can be one end of a colorchanging process as well. In other words, an indicator can appear ordisappear upon being triggered. Because the color changing is alsoenvironment dependent, the gloves will not pinpoint the exact time.Instead, a rough range is specified: less than 30 minutes, 30˜60minutes, and longer than 1 hour, and so on. Additionally, the indicatorcan show a first color at less than 30 minutes, a second color between30˜60 minutes, and a third color when longer than 1 hour. The colorchanging is gradual, and not a sharp change.

If the ink is added into the glove dipping compound, the whole glovewill change color over time. The ink can be sprayed on a certain portionof the glove. A company logo can be sprayed onto the glove and it can bemade to disappear as the indicator, or a message such as “time tochange” can be made to appear. The inks can also be provided separatelyfor glove wearers as stamps or self-stickers. The glove wearers canapply them at the time they put the gloves on, or as desired.

If the color changing is reversible, the manufacturing process andstorage requirement is very flexible. Otherwise, special precautionarymeasures have to be applied.

FIGS. 1 to 3 show the gloves with indicators incorporated therein. Theydemonstrate color change before and after activation, via varioustriggering mechanisms. FIG. 1 depicts a glove 10 having a coloredwarning symbol 14 changing from a first color, seen in FIG. 1 a to asecond color, seen in FIG. 1 b, indicating that the glove needs to bechanged. FIG. 2 a depicts a glove 10 having a warning symbol 16, whichmay be a message, appearing, as shown in FIG. 2 b to indicate that theglove need to be changed. This would work in reverse for a symbol thatdisappears when the glove needs to be changed. FIGS. 3 a-c shows aprogressive symbol 18 on glove 10 changing colors over time to give anindication of elapsed time. The glove displays a first color, shown inFIG. 1 a for the first 30 minutes of use, a second color seen in FIG. 3b from 30-60 minutes of use and a third color, seen in FIG. 3 c after 60minutes. For all embodiments, the colors displayed by the gloves are afunction of the material used for the warning sign.

The demonstrated methods can be applied to all disposable gloves, suchas natural rubber latex, nitrile butadiene rubber, polyisoprenepolychloroprene, polybutadiene rubber, butyl rubber, polyvinyl chloride,polyurethane, styrene ended copolymer thermal elastomers, as well astheir blends, copolymers, and multiple structured composites. Thesemethods are independent from the glove matrix materials involved and canbe applied to gloves either on-line or off-line. This gives greatflexibility to the glove manufacturers to implement the processes.

EXAMPLE 1 UV Sensitive Indicator

UV sensitive material, sometimes called photo chromatic material, issensitive to UV light. The color of the material changes when exposed toa UV light source, such as sunlight. When photo chromatic materials areexposed to UV light, they absorb the energy and use that energy tochange their molecular structures. The new structures will havedifferent color absorption and reflection abilities than the originalstructures. Thus, visible color changing occurs. This depends on thematerials used. A color change can also be altered and the time span forthe color change is adjustable. The color change process can bereversible, molecular structure changes back to original once UV lightis absent, or irreversible, once the molecular structure is changed byUV source, it remains at new form even when UV source is absent. Onepossible material usable as a UV sensitive indicator is a mixture of dyepigment and UV activated materials such as the spiro-indoline-oxazinesfamily, for example CTI Photo UV yellow, a commercially availablematerial from Chromatic Technologies, Inc.

EXAMPLE 2 Indoor Visible Light Sensitive Indicator

Similar to UV sensitive materials, fluorescent light sensitive materialsare sensitive to fluorescent light such as indoor visible light. Themechanism is very similar to the UV mechanism. The only difference isthat visible light activates the molecular structure change of thematerial, resulting in a visible color change. A different color changecan be achieved using different materials. Again, the color changeprocess can be reversible or irreversible and depends on differentchemicals used. One possible material usable as a visible lightsensitive indicator is a mixture of dye pigment and silver salts, forexample C WC Ag 1, a commercially available material from Spectra GroupLimited, Inc.

The glove manufacturing process is a little more difficult, in that theglove manufacturing operation can't be entirely in the dark. Indicatorswith lower wavelength activation, known as blue side, are preferred. Themanufacturing operation can be conducted with limited red lightexposure.

EXAMPLE 3 Carbon Dioxide (pH) Sensitive Indicator

There are many pH indictors used for acid base titration. One isthymolphthalein, colorless at pH<9.3 and dark blue at pH>10.5. Theindicator system also contains sodium hydroxide, a commonly used base.It adsorbs any accessible acidic substance. In the application to aglove, the indicator goes from dark blue to colorless. The chemicalreaction upon air exposure is as follows:

Although this reaction is reversible, strict avoidance of any acidicsubstances during manufacturing process is recommended and storage needsto be airtight. One possible material used as a carbon dioxide sensitiveindicator is a mixture of a pH indicator, such as thymolphthalein andbase or acid solution, such as sodium hydroxide and sold by PenguinMagic Inc. as Disappearing Ink.

EXAMPLE 4 Oxygen Sensitive Indicator

Indicators for oxidation-reduction titration can serve as timeindicators. Similar to carbon dioxide sensitive gloves, airtight storagehas to be adopted. One possible material used as a oxygen sensitiveindicator is a mixture of thiazone dye pigment and aliphatic organiccompounds, such as RP Systems oxygen indicators from MitsubishiChemicals.

EXAMPLE 5 Chemical Reaction Activated Indicator

Strictly speaking, all of the above indicators are activated by chemicalreaction. The glove has to gain an extra component from the environment;energy such as light or heat or components form the air such as oxygenand carbon dioxide.

The gloves can be made with certain components inside or on the a glove.They can provide some other ingredients separately as a self-sticker.The glove wearer can apply this self-sticker onto the glove after theglove is put on. Once the contact between the reactive ingredientsoccurs, the desired color change would result over a predeterminedperiod. This would allow a more flexible and friendly manufacturing andstorage requirement.

When the elapsed time is less than 30 minutes, the color is yellow.Gradually, it turns orange, the wearer would know the glove has beendonned for 30 to 60 minutes. If the color is pink, it means the glovehas been put on for longer than one hour. One possible material used asa chemical reaction activated indicator is a mixture of dye pigment,alkaline substance and ascorbic acid and salt, for example TT sensor, acommercially available chemical reaction activated indicator from AveryDennison.

EXAMPLE 6 Body Heat Activated Indicator

There are many heat sensitive indicators. However, many of them are notsuitable for application to a glove because the temperature of the glovewhile on wearer's hands should not dramatically change. However, anindicator that is dark blue at room temperature and turns light green atelevated temperature can be used. The color change occurs when thetemperature reaches ˜31° C., which is lower than body temperature. Theindicator is dark blue during normal storage conditions. After it hasbeen put on, the body temperature of the hand would turn the indicatorlight green in less than 30 minutes. One possible material used as abody heat activated indicator is a mixture of dye pigment, diaryl;phthalides and acidic phosphoric acid ester compounds, for example, SBScreen 31C, a commercially available ink from Chromatic Technologies,Inc.

We can also combine some of these methods and technologies. Forinstance, an oxidation-reduction titration indicator can be combinedwith a sodium chlorite. Upon light exposure, sodium chlorite willdecompose and release chlorine and chlorine dioxide. Both are strongoxidizers causing color change of many oxidation-reduction indicators.

The indicators can be single component and multiple components. It canbe entirely or partially embedded into a glove. It can have componentsseparately as self-stickers. It can be ingredients of a glove-dippingcompound and can be sprayed over the surface.

The visual change can be a simple color change from one color to anothercolor with one of the colors bring colorless, or a sign appearing ordisappearing. The color indication can be any symbol, a company logo, ora message and could encompass the entire glove.

1. A glove comprising a finger portion; a palm portion extending fromsaid finger portion; a back portion opposite said palm portion, and atime indicator signaling the time elapsed.
 2. The glove of claim 1,wherein said time indicator is a symbol appearing on said glove after apreselected period of time.
 3. The glove of claim 2, wherein said symbolis a text message.
 4. The glove of claim 1, wherein said time indicatoris a symbol on said glove disappearing after a preselected period oftime.
 5. The glove of claim 1, wherein said time indicator is on saidback portion.
 6. The glove of claim 1, wherein said time indicator isactivated by carbon dioxide, oxygen, visible light, ultraviolet light,heat, or a chemical reaction between two components.
 7. The glove ofclaim 6, wherein said time indicator is activated by carbon dioxide oroxygen.
 8. The glove of claim 6, wherein said time indicator isactivated by visible light or ultraviolet light.
 9. The glove of claim1, wherein said time indicator is a symbol having a first initial colorand a second color after a first time period has elapsed.
 10. The gloveof claim 9, wherein said symbol has a third color after a second timeperiod has elapsed.